Simpson Strong-Drive SDCP TIMBER-CP Screw - 8 mm x 140 mm, Black E-Coat by Simpson Strong-Tie is a structural timber fastener engineered for demanding cross-laminated timber (CLT), mass timber, and general interior wood framing applications. This partially threaded screw delivers exceptional pull-together force and load capacity across a wide range of engineered wood and multi-ply lumber assemblies. The black e-coat electrocoating finish provides a friction-reducing, nonmetallic surface that makes driving easier while also meeting corrosion resistance requirements for fire-retardant treated (FRT) lumber. Whether you are working on timber framing, post frame construction, factory-built or modular buildings, or structural composite lumber connections, this fastener is designed to perform without the need for predrilling in most applications.

Key Features

• Black e-coat electrocoating finish - provides a construction-durable, nonmetallic, friction-reducing surface approved for FRT lumber and corrosion resistance (ICC-ES AC257 Exposure Condition 3), reducing drive torque while protecting against corrosion in interior and dry-service environments
• Optimized hardness profile - mitigates external hydrogen embrittlement issues and meets CSA O86:24 requirements, giving builders confidence in structural integrity and long-term performance in timber construction
• Flat head with underhead nibs - helps countersink cleanly for a flush surface finish, reducing the need for additional surface prep and delivering a professional result on exposed timber faces
• Deep T40, 6-lobe recess - provides a secure, slip-resistant drive connection and includes a driver bit in the package so you can start work immediately without sourcing separate tooling
• Heavy-duty shank - adds strength and durability to the fastener body, supporting high structural loads in mass timber and engineered wood connections
• Shank knurl - aids in torque reduction during installation, making it easier to drive these screws consistently and reducing fatigue during high-volume framing work
• Type-17 point - ensures fast, clean starts, reduces installation torque, and eliminates the need for predrilling in most applications, saving time on structural timber jobsites
• Partial thread design - pulls structural members together with superior holding power, ideal for wood-to-wood fastening where tight clamping force is critical
• Length: 140 mm (5 1/2 in.) with a thread length of 3 1/8 in. - sized for solid engagement in thick timber members and multi-ply engineered wood assemblies

Why This Product

• Built specifically for mass timber and CLT construction - the SDCP Timber-CP screw addresses the unique structural demands of cross-laminated timber and engineered wood applications where standard wood screws may not meet load or embrittlement requirements.
• Reduces installation effort without compromising performance - the combination of black e-coat's low friction surface, shank knurl, and Type-17 point all work together to lower drive torque, letting crews work faster and with less fatigue across large timber framing projects.
• Compliant with current engineering standards - the optimized hardness profile meets CSA O86:24 hydrogen embrittlement requirements and the e-coat finish is approved under ICC-ES AC257 Exposure Condition 3, helping project teams satisfy structural and code compliance requirements.
• Designed for dry-service interior environments - the black e-coat finish is specifically rated for interior and dry-service conditions including FRT lumber, making this screw the right choice for factory-built, modular, and residential wood construction where corrosion exposure must still be managed.

Specifications

• Brand: Simpson Strong-Tie
• Product Name: Strong-Drive SDCP TIMBER-CP Screw
• Diameter: 8 mm
• Length: 5 1/2 in. (140 mm)
• Thread Length: 3 1/8 in.
• Shank Diameter: 0.225 in.
• Head Diameter: 0.575 in.
• Head Type: Flat Head with Nibs
• Drive Type: T40 6-Lobe
• Point Type: Type-17 Point
• Coating: E-coat Electrocoating
• Finish: E-coat Electrocoating
• Color: Black